The food additive known as carrageenan (E 407) may lead to serious health issues such as chronic inflammatory bowel disease, ulcers, and elevated blood sugar levels in animals. Recently, researchers conducted a study to examine how carrageenan affects the human digestive system and sugar metabolism, discovering that it may heighten the permeability of the small intestine, likely due to inflammation.
The food additive known as carrageenan (E 407) may lead to serious health issues such as chronic inflammatory bowel disease, ulcers, and elevated blood sugar levels in animals. Researchers from DZD have explored how carrageenan influences the human intestines and sugar metabolism, discovering increased permeability of the small intestine likely resulting from intestinal inflammation.
Carrageenan, also referred to as E 407, is commonly utilized in the food industry as an emulsifier and thickening component in many products. Research has indicated that this additive can cause chronic inflammatory bowel disease, ulcers, and heightened blood sugar levels in animals. Nevertheless, the implications of carrageenan for the risk of developing type 2 diabetes in humans remain unclear, prompting a clinical study led by DZD’s Professors Robert Wagner and Norbert Stefan.
Increased permeability of the small intestine
In this study, healthy young men with a BMI below 30 kg/m² (average BMI 24.5 kg/m²) consumed either carrageenan as part of their regular nutrition—amounting to roughly two to three times the daily consumption typically found in the USA—or a placebo. Both groups were monitored over two weeks. The findings revealed a rise in the permeability of the small intestine, which is likely due to gut inflammation.
“Our research indicates that, similar to findings in animal studies, the intake of carrageenan may impair the intestinal barrier function,” explains Prof. Robert Wagner. “This could result in long-term health effects and an increased likelihood of inflammatory conditions.”
Participants with higher body weight showed reduced insulin sensitivity
The main focus of the study was insulin sensitivity, which refers to how effectively the hormone insulin lowers blood sugar levels—this diminishes early on before type 2 diabetes sets in. Although carrageenan did not significantly alter insulin action in the 20 participants, the data suggested that individuals with greater body weight experienced a decrease in insulin effectiveness, particularly in the liver, with higher carrageenan intake. Additionally, overweight men tended to exhibit increased inflammatory markers in their blood and show inflammation signs in the hypothalamus, the section of the brain responsible for managing sugar metabolism and appetite with enhanced carrageenan consumption.
More investigation into the health effects of carrageenan is needed
“On average, our subjects were likely too healthy to display significant metabolic changes caused by carrageenan,” mentions Prof. Norbert Stefan. “However, older or overweight people could potentially be more affected. This necessitates further studies in these specific demographic groups.”
The researchers stress the urgent need for continued research on how carrageenan impacts human health. “Considering the extensive use of carrageenan in various foods, we must seriously evaluate potential health risks,” concludes Prof. Wagner. “Understanding the effects of food additives is essential for providing the public with informed health recommendations.”
